Crab meat is a great source of protein and vitamin B12. It's also low in saturated fat. Choose fat-free mayonnaise to cut back on fat but not on flavor.
Combine crabmeat, breadcrumbs, scallions, bell pepper, Old Bay seasoning, and ground red pepper (if using) in a medium bowl. Add mayonnaise and lemon juice; mix with a fork. Form mixture into 8 patties about 3 inches in diameter.
Heat oil in a medium skillet over medium heat. Fry crab cakes until browned on the bottom (about 4 minutes); turn and cook 4 more minutes, or until browned and an instant-read thermometer inserted into the crab cake reads 155°. Serve with lemon wedges, if desired.